diff --git a/acs/attribute_aggregator/core.py b/acs/attribute_aggregator/core.py
index c20646a..0b99578 100644
--- a/acs/attribute_aggregator/core.py
+++ b/acs/attribute_aggregator/core.py
@@ -260,11 +260,18 @@ def load_or_create_user_profile(user=None, no_cleanup=False):
                     % user)
                 profile = UserAttributeProfile.objects.get(user=user)
             except ObjectDoesNotExist:
-                profile = UserAttributeProfile(user=user)
-                profile.save()
-                logger.info('load_or_create_user_profile: \
-                    profile with id %s for user %s created' \
-                    % (str(profile.id), user))
+                try:
+                    profile = UserAttributeProfile(user=user)
+                    profile.save()
+                    logger.info('load_or_create_user_profile: \
+                        profile with id %s for user %s created' \
+                        % (str(profile.id), user))
+                except:
+                    profile = UserAttributeProfile()
+                    profile.save()
+                    logger.debug('load_or_create_user_profile: \
+                        profile with id %s for an anonymous user created' \
+                        % str(profile.id))
             else:
                 if no_cleanup:
                     logger.debug('load_or_create_user_profile: Existing user \
diff --git a/acs/attribute_aggregator/models.py b/acs/attribute_aggregator/models.py
index c7a523e..18e0a1f 100644
--- a/acs/attribute_aggregator/models.py
+++ b/acs/attribute_aggregator/models.py
@@ -26,6 +26,10 @@ from cPickle import loads, dumps
 from django.utils.translation import ugettext as _
 from django.db import models
 from django.contrib.auth.models import User
+try:
+    import ldap
+except ImportError:
+    ldap = None
 
 from acs.attribute_aggregator.signals import any_attributes_call, \
     listed_attributes_call, listed_attributes_with_source_call
@@ -77,37 +81,36 @@ def get_all_sources():
     except:
         return None
 
+if ldap:
+    class LdapSource(AttributeSource):
+        server = models.CharField(
+            verbose_name = _("Server"),
+            max_length=200, unique=True)
+        user = models.CharField(
+            verbose_name = _("User"),
+            max_length=200, blank=True, null=True)
+        password = models.CharField(
+            verbose_name = _("Password"),
+            max_length=200, blank=True, null=True)
+        base = models.CharField(
+            verbose_name = _("Base"),
+            max_length=200)
+        port = models.IntegerField(
+            verbose_name = _("Port"),
+            default=389)
+        ldaps = models.BooleanField(
+            verbose_name = _("LDAPS"),
+            default=False)
+        certificate = models.TextField(
+            verbose_name = _("Certificate"),
+            blank=True)
+        is_auth_backend = models.BooleanField(
+            verbose_name = _("Is it used for authentication?"),
+            default=False)
 
-class LdapSource(AttributeSource):
-    server = models.CharField(
-        verbose_name = _("Server"),
-        max_length=200, unique=True)
-    user = models.CharField(
-        verbose_name = _("User"),
-        max_length=200, blank=True, null=True)
-    password = models.CharField(
-        verbose_name = _("Password"),
-        max_length=200, blank=True, null=True)
-    base = models.CharField(
-        verbose_name = _("Base"),
-        max_length=200)
-    port = models.IntegerField(
-        verbose_name = _("Port"),
-        default=389)
-    ldaps = models.BooleanField(
-        verbose_name = _("LDAPS"),
-        default=False)
-    certificate = models.TextField(
-        verbose_name = _("Certificate"),
-        blank=True)
-    is_auth_backend = models.BooleanField(
-        verbose_name = _("Is it used for authentication?"),
-        default=False)
-
-    def __init__(self, *args, **kwargs):
-        super(LdapSource, self).__init__(*args, **kwargs)
-        self.namespace = "X500"
-
+        def __init__(self, *args, **kwargs):
+            super(LdapSource, self).__init__(*args, **kwargs)
+            self.namespace = "X500"
 
 class UserAliasInSource(models.Model):
     name = models.CharField(
diff --git a/acs/attribute_aggregator/signals.py b/acs/attribute_aggregator/signals.py
index 7e90ecc..a235590 100644
--- a/acs/attribute_aggregator/signals.py
+++ b/acs/attribute_aggregator/signals.py
@@ -18,7 +18,10 @@
 '''
 
 
-import ldap_sources
+try:
+    import ldap_sources
+except ImportError:
+    ldap_sources = None
 import user_profile
 
 from django.dispatch import Signal
@@ -29,9 +32,10 @@ listed_attributes_call = Signal(providing_args = ["user", "definitions"])
 listed_attributes_with_source_call = Signal(providing_args = \
     ["user", "definitions", "source"])
 
-any_attributes_call.connect(ldap_sources.get_attributes)
-listed_attributes_call.connect(ldap_sources.get_attributes)
-listed_attributes_with_source_call.connect(ldap_sources.get_attributes)
+if ldap_sources:
+    any_attributes_call.connect(ldap_sources.get_attributes)
+    listed_attributes_call.connect(ldap_sources.get_attributes)
+    listed_attributes_with_source_call.connect(ldap_sources.get_attributes)
 
 any_attributes_call.connect(user_profile.get_attributes)
 listed_attributes_call.connect(user_profile.get_attributes)